One of the common forms of jewelry clasps that are in use with necklaces are what is known in the trade as a box clasp, due primarily to the fact that it has a box-like body into which a spring member may be inserted. It is common for clasps of this nature to have at the end wall of the box-like casing, an aperture which is usually elongated so that it will receive a spring-like member. An example of this type of construction is seen in the Schick specification, U.S. Pat. No. 1,813,963, and in British Specification No. 130,222.
A difficulty in using this type of clasp is experienced by many individuals, for they find it difficult to place the catch in through the opening as this is being done, for the most part, "blind"--that is to say, while the clasp is in the back of one's neck. It is desirable, therefore, to have a clasp that is more readily inserted and released from a body so that ease of insertion and withdrawal is enhanced.